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Mechanism of Action

Aggrastat®  is a reversible antagonist of fibrinogen that binds to the glycoprotein (GP) IIb/IIIa receptor, the major platelet surface receptor involved in platelet aggregation.

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Aggrastat® HDB achieves >90% platelet aggregation inhibition within 10 minutes.1,2

Aggrastat® has a half-life of approximately 2 hours and is cleared primarily by the kidneys, predominantly as unchanged drug.

Following discontinuation of an infusion of Aggrastat®, ex vivo platelet aggregation returns to near baseline within 4 to 8 hours in approximately 90% of patients with coronary artery disease. There is no effect on clearance of tirofiban by sex, race, age, or hepatic impairment.
Aggrastat Pharmacy Mechanism Of Action

Aggrastat® inhibition of thrombus formation in vivo3

Thrombus and bleeding management is an important consideration in several clinical situations including interventional procedures. T-TAS (Total Thrombus formation Analysis System) is an automated microchip flow chamber system for the quantitative analysis of the thrombus formation process under blood flow conditions. T-TAS reproduces the in vivo thrombus formation process in an ex vivo system that uses the same substances that stimulate thrombus formation under physiological conditions.

Platelet thrombus formation under flow condition pre–and post-Aggrastat®3

No antiplatelet therapy


DAPT + Aggrastat®

DAPT = dual antiplatelet therapy

Platelet thrombus formation using T-TAS plus PL-chip in whole blood samples from a healthy subject.

Video-recorded images of the PL-chip in whole blood from an antiplatelet naïve subject, and with DAPT pre- and post-tirofiban. Blood samples were collected in benzylsulfonyl-D-Arg-Pro-4-amidinobenzylamide (BAPA).*

Fibrin-rich platelet thrombus formation under flow condition3

No antiplatelet therapy


DAPT + Aggrastat®

DAPT = dual antiplatelet therapy

Fibrin-rich platelet thrombus formation using T-TAS plus AR-chip in whole blood samples from healthy patients.

Video-recorded images of the AR-chip in whole blood from an antiplatelet naïve subject, and with DAPT pre and post-tirofiban are shown. Blood samples were collected in 3.2 % citrate tubes.*

Arterial flow shear
Venous flow shear
= 600s-1
Occlusion start time (min, secs) AUC Occlusion start time (min, secs) Occlusion time
Antiplatelet Naive 1:29 395 6:15 8:25 1821
DAPT (ASA 81 mg +
clopidogrel 75 mg)
4:42 231 5:38 7:26 1890
DAPT + tirofiban 10:00 21 18:28 20:00 835

DAPT = dual antiplatelet therapy; ASA = aspirin; AUC = area under the curve

* Methods. Blood was drawn from an antiplatelet naïve subject into Benzylsulfonyl-D-argininyl-prolyl-4-amidinobenzylamide (BAPA) and sodium citrate blood collection tubes and measured using the RUO T-TAS® plus system. A second blood collection was then performed in same subject following 3 days of DAPT with ASA 81 mg and clopidogrel 75 mg and blood was processed. Additional BAPA and citrate tubes were collected during a second blood draw and incubated with 100 ng/mL of tirofiban for 15 minutes and then processed. The results from both PL chip and AR chip analysis are included in Table (above).


1. Mardikar HM et al. Am Heart J 2007; 154:344e1-344e5
2. Danzi GB et al. AM J Cardiol 2006; 97:489-493
3. Credit. Kevin P. Bliden, Udaya S. Tantry, Paul A. Gurbel; Sinai Center for Thrombosis Research and Drug Development, Sinai Hospital of Baltimore, MD

Important Safety Information


Aggrastat® is indicated to reduce the rate of thrombotic cardiovascular events (combined endpoint of death, myocardial infarction, or refractory ischemia/repeat cardiac procedure) in patients with non-ST elevation acute coronary syndrome (NSTE-ACS).


  • Known hypersensitivity to any component of Aggrastat®.
  • History of thrombocytopenia with prior exposure to Aggrastat®.
  • Active internal bleeding, or history of bleeding diathesis, major surgical procedure or severe physical trauma within the previous month.

Warnings and Precautions:

  • Aggrastat® can cause serious bleeding. Most bleeding associated with Aggrastat® occurs at the arterial access site for cardiac catheterization. Minimize the use of traumatic or potentially traumatic procedures such as arterial and venous punctures, intramuscular injections, nasotracheal intubation, etc. Concomitant use of fibrinolytics, anticoagulants and antiplatelet drugs increases the risk of bleeding. If bleeding cannot be controlled, discontinue Aggrastat®.
  • Thrombocytopenia: discontinue Aggrastat® and heparin.

Adverse Reactions:

  • Bleeding is the most commonly reported adverse reaction.

For additional information, refer to the full Prescribing Information.

You are encouraged to report negative side effects of prescription drugs to the FDA.

Visit www.FDA.gov/medwatch
or call 1-800-FDA-1088.